10:30 AM - 10:52 AM
Application of Job-shop Model for Supply Chain Optimization Considering Payment Delay between Members
In this paper, we discuss supply chain optimization considering financial exchange between different plants and different partners. The financial exchange is considered as the cash flow exchanges between suppliers, retailers, manufacturers and all the partners of the supply chain. We study the flow of money in a supply chain where each supply chain partner receives money from the downstream partners and makes payments to the upstream partners. The target is to obtain trade-off solutions during the operational supply chain planning. To model the problem we chose the Job Shop theoretical model where each machine represents a supply chain member and jobs represent the product batches. Each member of the supply chain has its own cash amount available and uses it to pay the upstream partners (suppliers and/or plant). We develop an integer linear programming model for the static case where the future receipts from distributors, and the payment terms and amounts of all suppliers are known. The objective is to minimize the finish dates of all activities taking into account the financial constraints. The originality of our problem is the consideration of payment terms of different members of the supply chain. The proposed linear program is useful to obtain optimal solutions on small and medium industrial instances. The benefits of this work are shown through a small case study that illustrates the modeling approach and procedures necessary to implement a financial/supply chain scheduling methodology to aid the high level staff during planning and budgeting activities.
10:52 AM - 11:14 AM
Tabu Search for Assembly/Disassembly Network Design
This article develops a tabu search algorithm to solve an optimal design problem of assembly/disassembly manufacturing networks. The objective is to maximize production rate subject to a total cost constraint. Machines are chosen from a list of products available in the market and sizes of the buffers are chosen within a predetermined range. The buffers are characterized by their cost coefficients associated with the buffer size. The machines are characterized by their cost, failure rate, repair rate and processing time. To estimate assembly/disassembly network performance, a decomposition-type approximation is used. The optimal design problem is formulated as a combinatorial optimization one where the decision variables are buffers and types of machines. The design problem, solved in this study, has been previously analyzed using genetic algorithms and harmony search. The proposed tabu search takes advantage of the use of a bottleneck identification procedure. Comparisons show that the proposed tabu search out-performs genetic
algorithms and harmony search solutions.
11:14 AM - 11:36 AM
A CAT Metaheuristic for the Design of Activity-Based Supply Chain Networks under Uncertainty
An approach to design resilient and effective supply chain networks operating under uncertainty is presented. A generic stochastic programming model with recourse based on the supply chain activity graph, on structural deployment options and on second stage procurement, production and distribution decisions is first formulated. A Collaborating Agent Team (CAT) metaheuristic developed to solve large instances of this model is then proposed. Numerical results for a number of test problems are finally presented.
11:36 AM - 11:58 AM
Suppliers' Coordination of Production and Delivery Decisions under Batch Size Constraints
We consider the problem of coordinating production and delivery of a set of products ordered by a unique customer to different suppliers. Each supplier is producing the ordered quantity of one of the products. Each supplier is incurring an inventory cost per product item per unit of time from time 0 until the shipping time of the item, and a fixed delivery cost per loaded truck. For economic reasons, the customer may accept to receive an ordered quantity split on many deliveries of small batches provided that each delivered quantity is greater than or equal to a minimum quantity threshold. Besides, delivered quantities must be less than or equal to a full truckload. The group of suppliers is considering mutualizing their deliveries. Deliveries mutualization supposes that the suppliers are synchronizing their deliveries, each of them contributing to all delivery batches. In this paper, we study this cooperative model and provide solution algorithms.